Search results for: direct shear test
2962 SVM Based Model as an Optimal Classifier for the Classification of Sonar Signals
Authors: Suresh S. Salankar, Balasaheb M. Patre
Abstract:
Research into the problem of classification of sonar signals has been taken up as a challenging task for the neural networks. This paper investigates the design of an optimal classifier using a Multi layer Perceptron Neural Network (MLP NN) and Support Vector Machines (SVM). Results obtained using sonar data sets suggest that SVM classifier perform well in comparison with well-known MLP NN classifier. An average classification accuracy of 91.974% is achieved with SVM classifier and 90.3609% with MLP NN classifier, on the test instances. The area under the Receiver Operating Characteristics (ROC) curve for the proposed SVM classifier on test data set is found as 0.981183, which is very close to unity and this clearly confirms the excellent quality of the proposed classifier. The SVM classifier employed in this paper is implemented using kernel Adatron algorithm is seen to be robust and relatively insensitive to the parameter initialization in comparison to MLP NN.
Keywords: Classification, MLP NN, backpropagation algorithm, SVM, Receiver Operating Characteristics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18192961 Research on Hybrid Neural Network in Intrusion Detection System
Authors: Jianhua Wang, Yan Yu
Abstract:
This paper presents an intrusion detection system of hybrid neural network model based on RBF and Elman. It is used for anomaly detection and misuse detection. This model has the memory function .It can detect discrete and related aggressive behavior effectively. RBF network is a real-time pattern classifier, and Elman network achieves the memory ability for former event. Based on the hybrid model intrusion detection system uses DARPA data set to do test evaluation. It uses ROC curve to display the test result intuitively. After the experiment it proves this hybrid model intrusion detection system can effectively improve the detection rate, and reduce the rate of false alarm and fail.
Keywords: RBF, Elman, anomaly detection, misuse detection, hybrid neural network.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23262960 Lateral Torsional Buckling of an Eccentrically Loaded Channel Section Beam
Authors: L. Dahmani, S. Drizi, M. Djemai, A. Boudjemia, M. O. Mechiche
Abstract:
Channel sections are widely used in practice as beams. However, design rules for eccentrically loaded (not through shear center) beams with channel cross- sections are not available in Eurocode 3. This paper compares the ultimate loads based on the adjusted design rules for lateral torsional buckling of eccentrically loaded channel beams in bending to the ultimate loads obtained with Finite Element (FE) simulations on the basis of a parameter study. Based on the proposed design rule, this study has led to a new design rule which conforms to Eurocode 3.Keywords: ANSYS, Eurocode 3, finite element method, lateral torsional buckling, steel channel beam.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30492959 A Comparative Study of Force Prediction Models during Static Bending Stage for 3-Roller Cone Frustum Bending
Authors: Mahesh Chudasama, Harit Raval
Abstract:
Conical sections and shells of metal plates manufactured by 3-roller conical bending process are widely used in the industries. The process is completed by first bending the metal plates statically and then dynamic roller bending sequentially. It is required to have an analytical model to get maximum bending force, for optimum design of the machine, for static bending stage. Analytical models assuming various stress conditions are considered and these analytical models are compared considering various parameters and reported in this paper. It is concluded from the study that for higher bottom roller inclination, the shear stress affects greatly to the static bending force whereas for lower bottom roller inclination it can be neglected.
Keywords: Roller-bending, static-bending, stress-conditions, analytical-modeling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10442958 Prestressed Concrete Girder Bridges Using Large 0.7 Inch Strands
Authors: Amin Akhnoukh
Abstract:
The National Bridge Inventory (NBI) includes more than 600,000 bridges within the United States of America. Prestressed concrete girder bridges represent one of the most widely used bridge systems. The majority of these girder bridges were constructed using 0.5 and 0.6 inch diameter strands. The main impediments to using larger strand diameters are: 1) lack of prestress bed capacities, 2) lack of structural knowledge regarding the transfer and development length of larger strands, and 3) the possibility of developing wider end zone cracks upon strand release. This paper presents a study about using 0.7 inch strands in girder fabrication. Transfer and development length were evaluated, and girders were fabricated using 0.7 inch strands at different spacings. Results showed that 0.7 inch strands can be used at 2.0 inch spacing without violating the AASHTO LRFD Specifications, while attaining superior performance in shear and flexure.
Keywords: 0.7 inch strands, prestress, I-girders, bridges
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30512957 Derivation of Monotone Likelihood Ratio Using Two Sided Uniformly Normal Distribution Techniques
Authors: D. A. Farinde
Abstract:
In this paper, two-sided uniformly normal distribution techniques were used in the derivation of monotone likelihood ratio. The approach mainly employed the parameters of the distribution for a class of all size a. The derivation technique is fast, direct and less burdensome when compared to some existing methods.
Keywords: Neyman-Pearson Lemma, Normal distribution
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32012956 Experimental Inspection of Damage and Performance Evaluation after Repair and Strengthening of Jiamusi Highway Prestressed Concrete Bridge in China
Authors: Ali Fadhil Naser, Wang Zonglin
Abstract:
The main objectives of this study are to inspect and identify any damage of jaimusi highway prestressed concrete bridge after repair and strengthening of damaged structural members and to evaluate the performance of the bridge structural members by adopting static load test. Inspection program after repair and strengthening includes identifying and evaluating the structural members of bridge such as T-shape cantilever structure, hanging beams, corbels, external tendons, anchor beams, sticking steel plate, and piers. The results of inspection show that the overall state of the bridge structural member after repair and strengthening is good. The results of rebound test of concrete strength show that the average strength of concrete is 46.31Mpa. Whereas, the average value of concrete strength of anchor beam is 49.82Mpa. According to the results of static load test, the experimental values are less than theoretical values of internal forces, deflection, and strain, indicating that the stiffness of the experimental structure, overall deformation and integrity satisfy the designed standard and the working performance is good, and the undertaking capacity has a certain surplus. There is not visible change in the length and width of cracks and there are not new cracks under experimental load.Keywords: Jiamusi Bridge, Damage inspection, deflection, strain.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18122955 The Impact of Drama Education on Creativity Development at Preschool Children
Authors: Vladimíra Hornáčková
Abstract:
This paper points out at the importance of creativity development in children of preschool age and analyses certain conditions and pedagogical principles which should be respected during the development of creativity in kindergartens. Research survey focuses on the development of creativity reflection at children in kindergartens at preschool age and based on a test of creativity it compares creativity of children in experimental and control groups. The goal is to find out if there are any differences among children in experimental and control classrooms in kindergartens; wherein experimental groups, there is preschool education with the use of drama education while in control groups there is not. On the basis of certain aspects, the gained data is compared through descriptive methods and correlations. Research results refer to reserves in creativity development in modern pre-primary education in the context of implemented and expected changes in didactic approach in the education of kindergartens.
Keywords: Preschool child, drama in education, research, test of creativity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18892954 Fluidity of A713 Cast Alloy with and without Scrap Addition using Double Spiral Fluidity Test: A Comparison
Authors: A.K. Birru, D Benny Karunakar, M. M. Mahapatra
Abstract:
Recycling of aluminum alloys often decrease fluidity, consequently influence the castability of the alloy. In this study, the fluidity of Al-Zn alloys, such as the standard A713 alloy with and without scrap addition has been investigated. The scrap added was comprised of contaminated alloy turning chips. Fluidity measurements were performed with double spiral fluidity test consisting of gravity casting of double spirals in green sand moulds with good reproducibility. The influence of recycled alloy on fluidity has been compared with that of the virgin alloy and the results showed that the fluidity decreased with the increase in recycled alloy at minimum pouring temperatures. Interestingly, an appreciable improvement in the fluidity was observed at maximum pouring temperature, especially for coated spirals.Keywords: A713 alloy, Fluidity, Hexachloroethane, Pouring temperature, Recycling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24912953 Design and Implementation of TMS320C31 DSP and FPGA for Conventional Direct Torque Control (DTC) of Induction Machines
Authors: C. L. Toh, N. R. N. Idris, A. H. M. Yatim
Abstract:
This paper introduces a new digital logic design, which combines the DSP and FPGA to implement the conventional DTC of induction machine. The DSP will be used for floating point calculation whereas the FPGA main task is to implement the hysteresis-based controller. The emphasis is on FPGA digital logic design. The simulation and experimental results are presented and summarized.Keywords: DTC, DSP, FPGA, induction machine
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19822952 Winged Test Rocket with Fully Autonomous Guidance and Control for Realizing Reusable Suborbital Vehicle
Authors: Koichi Yonemoto, Hiroshi Yamasaki, Masatomo Ichige, Yusuke Ura, Guna S. Gossamsetti, Takumi Ohki, Kento Shirakata, Ahsan R. Choudhuri, Shinji Ishimoto, Takashi Mugitani, Hiroya Asakawa, Hideaki Nanri
Abstract:
This paper presents the strategic development plan of winged rockets WIRES (WInged REusable Sounding rocket) aiming at unmanned suborbital winged rocket for demonstrating future fully reusable space transportation technologies, such as aerodynamics, Navigation, Guidance and Control (NGC), composite structure, propulsion system, and cryogenic tanks etc., by universities in collaboration with government and industries, as well as the past and current flight test results.Keywords: Autonomous guidance and control, reusable rocket, space transportation system, suborbital vehicle, winged rocket.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25522951 Numerical Simulation of Minimum Distance Jet Impingement Heat Transfer
Authors: Aman Agarwal, Georg Klepp
Abstract:
Impinging jets are used in various industrial areas as a cooling and drying technique. The current research is concerned with the means of improving the heat transfer for configurations with a minimum distance of the nozzle to the impingement surface. The impingement heat transfer is described using numerical methods over a wide range of parameters for an array of planar jets. These parameters include varying jet flow speed, width of nozzle, distance of nozzle, angle of the jet flow, velocity and geometry of the impingement surface. Normal pressure and shear stress are computed as additional parameters. Using dimensionless characteristic numbers the parameters and the results are correlated to gain generalized equations. The results demonstrate the effect of the investigated parameters on the flow.Keywords: Heat Transfer Coefficient, Minimum distance jet impingement, Numerical simulation, Dimensionless coefficients.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23532950 Localized and Time-Resolved Velocity Measurements of Pulsatile Flow in a Rectangular Channel
Authors: R. Blythman, N. Jeffers, T. Persoons, D. B. Murray
Abstract:
The exploitation of flow pulsation in micro- and mini-channels is a potentially useful technique for enhancing cooling of high-end photonics and electronics systems. It is thought that pulsation alters the thickness of the hydrodynamic and thermal boundary layers, and hence affects the overall thermal resistance of the heat sink. Although the fluid mechanics and heat transfer are inextricably linked, it can be useful to decouple the parameters to better understand the mechanisms underlying any heat transfer enhancement. Using two-dimensional, two-component particle image velocimetry, the current work intends to characterize the heat transfer mechanisms in pulsating flow with a mean Reynolds number of 48 by experimentally quantifying the hydrodynamics of a generic liquid-cooled channel geometry. Flows circulated through the test section by a gear pump are modulated using a controller to achieve sinusoidal flow pulsations with Womersley numbers of 7.45 and 2.36 and an amplitude ratio of 0.75. It is found that the transient characteristics of the measured velocity profiles are dependent on the speed of oscillation, in accordance with the analytical solution for flow in a rectangular channel. A large velocity overshoot is observed close to the wall at high frequencies, resulting from the interaction of near-wall viscous stresses and inertial effects of the main fluid body. The steep velocity gradients at the wall are indicative of augmented heat transfer, although the local flow reversal may reduce the upstream temperature difference in heat transfer applications. While unsteady effects remain evident at the lower frequency, the annular effect subsides and retreats from the wall. The shear rate at the wall is increased during the accelerating half-cycle and decreased during deceleration compared to steady flow, suggesting that the flow may experience both enhanced and diminished heat transfer during a single period. Hence, the thickness of the hydrodynamic boundary layer is reduced for positively moving flow during one half of the pulsation cycle at the investigated frequencies. It is expected that the size of the thermal boundary layer is similarly reduced during the cycle, leading to intervals of heat transfer enhancement.Keywords: Heat transfer enhancement, particle image velocimetry, localized and time-resolved velocity, photonics and electronics cooling, pulsating flow, Richardson’s annular effect.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23042949 Auto Tuning of PID Controller for MIMO Processes
Authors: M. J. Lengare, R. H. Chile, L. M. Waghmare, Bhavesh Parmar
Abstract:
One of the most basic functions of control engineers is tuning of controllers. There are always several process loops in the plant necessitate of tuning. The auto tuned Proportional Integral Derivative (PID) Controllers are designed for applications where large load changes are expected or the need for extreme accuracy and fast response time exists. The algorithm presented in this paper is used for the tuning PID controller to obtain its parameters with a minimum computing complexity. It requires continuous analysis of variation in few parameters, and let the program to do the plant test and calculate the controller parameters to adjust and optimize the variables for the best performance. The algorithm developed needs less time as compared to a normal step response test for continuous tuning of the PID through gain scheduling.Keywords: Auto tuning; gain scheduling; MIMO Processes; Optimization; PID controller; Process Control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30082948 Effect of Cladding and Secondary Members on the Elastic Stability of Main Columns
Authors: Mohamed Massoud El Sadaawy, Ehab Hasan Ahmed Hasan Ali
Abstract:
The corrugated steel cladding used to cover most of steel buildings is considered as non-structural element. This research will reflect the effect of cladding as a shear diaphragm in increasing the normal elastic capacity of columns. This study is important because of the lack of information of the behavior of cladding and secondary members in various codes. Mathematical models for six different cases are carried by software. The results extracted from the program have been plotted showing the effects of different variables on the ultimate load of column. The variables considered in our research are the spacing between columns and the thickness of the corrugated sheet representing the sheet stiffness.Keywords: Stability of frames about minor axis, The effective length factor, Effect of secondary members on elastic buckling load column, The stiffness of sheeting.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27962947 Utilization of Agro-Industrial Waste in Metal Matrix Composites: Towards Sustainability
Authors: L. Lancaster, M. H. Lung, D. Sujan
Abstract:
The application of agro-industrial waste in Aluminum Metal Matrix Composites has been getting more attention as they can reinforce particles in metal matrix which enhance the strength properties of the composites. In addition, by applying these agroindustrial wastes in useful way not only save the manufacturing cost of products but also reduce the pollutions on environment. This paper represents a literature review on a range of industrial wastes and their utilization in metal matrix composites. The paper describes the synthesis methods of agro-industrial waste filled metal matrix composite materials and their mechanical, wear, corrosion, and physical properties. It also highlights the current application and future potential of agro-industrial waste reinforced composites in aerospace, automotive and other construction industries.Keywords: Bond layer, Interfacial shear stress, Bi-layered assembly, Thermal mismatch, Flip Chip Ball Grid Array.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 45832946 Stochastic Estimation of Cavity Flowfield
Authors: Yin Yin Pey, Leok Poh Chua, Wei Long Siauw
Abstract:
Linear stochastic estimation and quadratic stochastic estimation techniques were applied to estimate the entire velocity flow-field of an open cavity with a length to depth ratio of 2. The estimations were done through the use of instantaneous velocity magnitude as estimators. These measurements were obtained by Particle Image Velocimetry. The predicted flow was compared against the original flow-field in terms of the Reynolds stresses and turbulent kinetic energy. Quadratic stochastic estimation proved to be more superior than linear stochastic estimation in resolving the shear layer flow. When the velocity fluctuations were scaled up in the quadratic estimate, both the time-averaged quantities and the instantaneous cavity flow can be predicted to a rather accurate extent.Keywords: Open cavity, Particle Image Velocimetry, Stochastic estimation, Turbulent kinetic energy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17112945 Investigation Bubble Growth and Nucleation Rates during the Pool Boiling Heat Transfer of Distilled Water Using Population Balance Model
Authors: V. Nikkhah Rashidabad, M. Manteghian, M. Masoumi, S. Mousavian
Abstract:
In this research, the changes in bubbles diameter and number that may occur due to the change in heat flux of pure water during pool boiling process. For this purpose, test equipment was designed and developed to collect test data. The bubbles were graded using Caliper Screen software. To calculate the growth and nucleation rates of bubbles under different fluxes, population balance model was employed. The results show that the increase in heat flux from q=20 kw/m2 to q= 102 kw/m2 raised the growth and nucleation rates of bubbles.
Keywords: Heat flux, bubble growth, bubble nucleation, population balance model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24662944 Preparation of Homogeneous Dense Composite of Zirconia and Alumina (ZTA)using Colloidal Filtration
Authors: H. Wakily, M. Mehrali, H. S. C. Metselaar
Abstract:
Homogeneous composites of alumina and zirconia with a small amount of MgO (<1 wt %) were prepared by colloidal filtration. The object of using ZrO2 (15wt %) was to provide zirconia toughened alumina (ZTA). Suspensions of alumina and Zirconia with various solid loadings and various concentrations of Dolapix CE64 as surfactant were studied. The stability of these suspensions was investigated using rheological measurements. The optimum amount of using Dolapix was 0.8wt% for ZTA containing MgO suspension which gave low apparent viscosity in basic area (100 mPa s at shear rate of 50 s-1). The satisfactory mixtures were made into sample pallets using colloidal filtration. The process was completed with pressureless sintering in suitable temperature. Phase, grain size and qualitative compositional analysis were done using X-ray diffraction (XRD) and scanning electron microscopy (SEM) images. ZTA containing 0.05 wt% MgO shows the lowest grain size for alumina around 0.5 μm. Densification studies show that near full densities (>99%) were obtained for ZTA ceramic containing 0.05 wt% MgO in 1500 °C.Keywords: Colloidal filtration, Dolapix, MgO, Zirconiatoughened alumina.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29912943 Heating and Cooling Scenario of Blended Concrete Subjected to 780 Degrees Celsius
Authors: J. E. Oti, J. M. Kinuthia, R. Robinson, P. Davies
Abstract:
In this study, the Compressive strength of concretes made with Ground Granulated Blast furnace Slag (GGBS), Pulverised Fuel Ash (PFA), Rice Husk Ash (RHA) and Waste Glass Powder (WGP) after they were exposed 7800C (exposure duration of around 60 minutes) and then allowed to cool down gradually in the furnace for about 280 minutes at water binder ratio of 0.50 was investigated. GGBS, PFA, RHA and WGP were used to replace up to 20% Portland cement in the control concrete. Test for the determination of workability, compressive strength and tensile splitting strength of the concretes were carried out and the results were compared with control concrete. The test results showed that the compressive strength decreased by an average of around 30% after the concretes were exposed to the heating and cooling scenario.
Keywords: Pulverised Fuel Ash, Rice Husk Ash, heating and cooling, concrete.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17832942 Mean Velocity Modeling of Open-Channel Flow with Submerged Rigid Vegetation
Authors: M. Morri, A. Soualmia, P. Belleudy
Abstract:
Vegetation affects the mean and turbulent flow structure. It may increase flood risks and sediment transport. Therefore, it is important to develop analytical approaches for the bed shear stress on vegetated bed, to predict resistance caused by vegetation. In the recent years, experimental and numerical models have both been developed to model the effects of submerged vegetation on open-channel flow. In this paper, different analytic models are compared and tested using the criteria of deviation, to explore their capacity for predicting the mean velocity and select the suitable one that will be applied in real case of rivers. The comparison between the measured data in vegetated flume and simulated mean velocities indicated, a good performance, in the case of rigid vegetation, whereas, Huthoff model shows the best agreement with a high coefficient of determination (R2=80%) and the smallest error in the prediction of the average velocities.
Keywords: Analytic Models, Comparison, Mean Velocity, Vegetation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25362941 Numerical Analysis and Experimental Validation of Detector Pressure Housing Subject to HPHT
Authors: Hafeez Syed, Harit Naik
Abstract:
Reservoirs with high pressures and temperatures (HPHT) that were considered to be atypical in the past are now frequent targets for exploration. For downhole oilfield drilling tools and components, the temperature and pressure affect the mechanical strength. To address this issue, a finite element analysis (FEA) for 206.84 MPa (30 ksi) pressure and 165°C has been performed on the pressure housing of the measurement-while-drilling/logging-whiledrilling (MWD/LWD) density tool. The density tool is a MWD/LWD sensor that measures the density of the formation. One of the components of the density tool is the pressure housing that is positioned in the tool. The FEA results are compared with the experimental test performed on the pressure housing of the density tool. Past results show a close match between the numerical results and the experimental test. This FEA model can be used for extreme HPHT and ultra HPHT analyses, and/or optimal design changes.Keywords: FEA, HPHT, M/LWD, Oil & Gas
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16412940 Satisfaction of Distance Education University Students with the Use of Audio Media as a Medium of Instruction: The Case of Mountains of the Moon University in Uganda
Authors: Mark Kaahwa, Chang Zhu, Moses Muhumuza
Abstract:
This study investigates the satisfaction of distance education university students (DEUS) with the use of audio media as a medium of instruction. Studying students’ satisfaction is vital because it shows whether learners are comfortable with a certain instructional strategy or not. Although previous studies have investigated the use of audio media, the satisfaction of students with an instructional strategy that combines radio teaching and podcasts as an independent teaching strategy has not been fully investigated. In this study, all lectures were delivered through the radio and students had no direct contact with their instructors. No modules or any other material in form of text were given to the students. They instead, revised the taught content by listening to podcasts saved on their mobile electronic gadgets. Prior to data collection, DEUS received orientation through workshops on how to use audio media in distance education. To achieve objectives of the study, a survey, naturalistic observations and face-to-face interviews were used to collect data from a sample of 211 undergraduate and graduate students. Findings indicate that there was no statistically significant difference in the levels of satisfaction between male and female students. The results from post hoc analysis show that there is a statistically significant difference in the levels of satisfaction regarding the use of audio media between diploma and graduate students. Diploma students are more satisfied compared to their graduate counterparts. T-test results reveal that there was no statistically significant difference in the general satisfaction with audio media between rural and urban-based students. And ANOVA results indicate that there is no statistically significant difference in the levels of satisfaction with the use of audio media across age groups. Furthermore, results from observations and interviews reveal that DEUS found learning using audio media a pleasurable medium of instruction. This is an indication that audio media can be considered as an instructional strategy on its own merit.
Keywords: Audio media, distance education, distance education university students, medium of instruction, satisfaction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7972939 Seismic Analysis of Structurally Hybrid Wind Mill Tower
Authors: Atul K. Desai, Hemal J. Shah
Abstract:
The tall windmill towers are designed as monopole tower or lattice tower. In the present research, a 125-meter high hybrid tower which is a combination of lattice and monopole type is proposed. The response of hybrid tower is compared with conventional monopole tower. The towers were analyzed in finite element method software considering nonlinear seismic time history load. The synthetic seismic time history for different soil is derived using the SeismoARTIF software. From the present research, it is concluded that, in the hybrid tower, we are not getting resonance condition. The base shear is less in hybrid tower compared to monopole tower for different soil conditions.
Keywords: Dynamic analysis, hybrid wind mill tower, resonance condition, synthetic time history.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7572938 Average Turbulent Pipe Flow with Heat Transfer Using a Three-Equation Model
Authors: Khalid Alammar
Abstract:
Aim of this study is to evaluate a new three-equation turbulence model applied to flow and heat transfer through a pipe. Uncertainty is approximated by comparing with published direct numerical simulation results for fully-developed flow. Error in the mean axial velocity, temperature, friction, and heat transfer is found to be negligible.
Keywords: Heat Transfer, Nusselt number, Skin friction, Turbulence.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24462937 Experimental Investigation of the Influence of Cement on Soil-Municipal Solid Incineration Fly Ash Mix Properties
Authors: G. Aouf, D. Tabbal, A. Sabsabi, R. Aouf
Abstract:
The aim of this study is to assess the viability of utilizing Municipal Solid Waste Incineration Fly Ash (MSWIFA) with Ordinary Portland cement as soil reinforcement materials for geotechnical engineering applications. A detailed experimental program is carried out followed by analysis of results. Soil samples were prepared by adding cement to MSWIFA-soil mix at different percentages. Then, a series of laboratory tests were performed namely: Sieve analysis, Atterberg limits tests, Unconfined compression test, and Proctor tests. A parametric study is conducted to investigate the effect of adding the cement at different percentages on the unconfined compression strength, maximum dry density (MDD), and optimum moisture content (OMC) of clayey soil-MSWIFA. The variations of admixtures’ contents were 10%, 20%, and 30% for MSWIFA by dry total weight of soil and 10%, 15%, and 20% for Portland cement by dry total weight of the mix. The test results reveal that adding MSWIFA to the soil up to 20% increased the MDD of the mixture and decreased the OMC, then an opposite trend for results were found when the percentage of MSWIFA exceeds 20%. This is due to the low specific gravity of MSWIFA and to the greater water absorption of MSWIFA. The laboratory tests also indicate that the Unconfined Compression Test values were found to be increased for all the mixtures with curing periods of 7, 14, and 28 days. It is also observed that the cement increased the strength of the finished product of the mix of soil and MSWIFA.
Keywords: Clayey soil, cement, Municipal Solid Waste Incineration Fly Ash, MSWIFA, unconfined compression strength.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3472936 Electroencephalography Activity during Sensory Organization Balance Test
Authors: Tariq Ali Gujar, Anita Hökelmann
Abstract:
Postural balance plays essential role throughout life in daily activities. Somatosensory, visual and vestibular inputs play the fundamental role in maintaining body equilibrium to balance the posture. The aim of this study was to find out electroencephalography (EEG) responses during balance activity of young people during Sensory Organization Balance Test. The outcome of this study will help to create the fitness and neurorehabilitation plan. 25 young people (25 ± 3.1 years) have been analyzed on Balance Master NeuroCom® with the coupling of Brain Vision 32 electrode wireless EEG system during the Sensory Organization Test. From the results it has been found that the balance score of samples is significantly higher under the influence of somatosensory input as compared to visual and vestibular input (p < 0.05). The EEG between somatosensory and visual input to balance the posture showed significantly higher (p < 0.05) alpha and beta activities during somatosensory input in somatosensory, attention and visual functions of the cortex whereas executive and motor functions of the cerebral cortex showed significantly higher (p < 0.05) alpha EEG activity during the visual input. The results suggest that somatosensory and attention function of the cerebral cortex has alpha and beta activity, respectively high during somatosensory and vestibular input in maintaining balance. In patients with balance impairments both physical and cognitive training, including neurofeedback will be helpful to improve balance abilities.
Keywords: Balance, electroencephalography activity, somatosensory, visual, vestibular.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6082935 Antiinflammatory and Antinociceptive of Hydro Alcoholic Tanacetum balsamita L. Extract
Authors: S. Nasri, G. H. Amin, A. Azimi
Abstract:
The use of herbs to treat disease is accompanied with the history of human life. This research is aimed to study the anti-inflammatory and antinociceptive effects of hydroalcoholic extract of aerial parts of "Tanacetum balsamita balsamita". In the experimental studies 144 male mice are used. In the inflammatory test, animals were divided into six groups: Control, positive control (receiving Dexamethason at dose of 15mg/kg), and four experimental groups receiving Tanacetum balsamita balsamita hydroalcoholic extract at doses of 25, 50, 100 and 200mg/kg. Xylene was used to induce inflammation. Formalin was used to study the nociceptive effects. Animals were divided into six groups: control group, positive control group (receiving morphine) and four experimental groups receiving Tanacetum balsamita balsamita (Tb.) hydroalcoholic extract at doses of 25, 50, 100 and 200mg/kg. I.p. injection of drugs or normal saline was performed 30 minutes before test. The data were analyzed by using one way Variance analysis and Tukey post test. Aerial parts of Tanacetum balsamita balsamita hydroalcoholic extract decreased significantly inflammatory at dose of 200mg/kg (P<0/001) and caused a significant decrease and alleviated the nociception in both first and second phases at doses of 200mg/kg (p<0/001) and 100mg/kg (P<0/05). Tanacetum balsamita balsamita extract has the anti-inflammatory and anti-nociceptive effects which seems to be related with flavonoids especially Quercetin.
Keywords: Inflammation, nociception, Hydroalcoholic extract, aerial parts of Tanacetum balsamita balsamita L.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20932934 Investigating Interference Errors Made by Azzawia University 1st year Students of English in Learning English Prepositions
Authors: Aimen Mohamed Almaloul
Abstract:
The main focus of this study is investigating the interference of Arabic in the use of English prepositions by Libyan university students. Prepositions in the tests used in the study were categorized, according to their relation to Arabic, into similar Arabic and English prepositions (SAEP), dissimilar Arabic and English prepositions (DAEP), Arabic prepositions with no English counterparts (APEC), and English prepositions with no Arabic counterparts (EPAC).
The subjects of the study were the first year university students of the English department, Sabrata Faculty of Arts, Azzawia University; both males and females, and they were 100 students. The basic tool for data collection was a test of English prepositions; students are instructed to fill in the blanks with the correct prepositions and to put a zero (0) if no preposition was needed. The test was then handed to the subjects of the study.
The test was then scored and quantitative as well as qualitative results were obtained. Quantitative results indicated the number, percentages and rank order of errors in each of the categories and qualitative results indicated the nature and significance of those errors and their possible sources. Based on the obtained results the researcher could detect that students made more errors in the EPAC category than the other three categories and these errors could be attributed to the lack of knowledge of the different meanings of English prepositions. This lack of knowledge forced the students to adopt what is called the strategy of transfer.
Keywords: Foreign language acquisition, foreign language learning, interference system, interlanguage system, mother tongue interference.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 50452933 An Automated Test Setup for the Characterization of Antenna in CATR
Authors: Faisal Amin, Abdul Mueed, Xu Jiadong
Abstract:
This paper describes the development of a fully automated measurement software for antenna radiation pattern measurements in a Compact Antenna Test Range (CATR). The CATR has a frequency range from 2-40 GHz and the measurement hardware includes a Network Analyzer for transmitting and Receiving the microwave signal and a Positioner controller to control the motion of the Styrofoam column. The measurement process includes Calibration of CATR with a Standard Gain Horn (SGH) antenna followed by Gain versus angle measurement of the Antenna under test (AUT). The software is designed to control a variety of microwave transmitter / receiver and two axis Positioner controllers through the standard General Purpose interface bus (GPIB) interface. Addition of new Network Analyzers is supported through a slight modification of hardware control module. Time-domain gating is implemented to remove the unwanted signals and get the isolated response of AUT. The gated response of the AUT is compared with the calibration data in the frequency domain to obtain the desired results. The data acquisition and processing is implemented in Agilent VEE and Matlab. A variety of experimental measurements with SGH antennas were performed to validate the accuracy of software. A comparison of results with existing commercial softwares is presented and the measured results are found to be within .2 dBm.Keywords: Antenna measurement, calibration, time-domain gating, VNA, Positioner controller
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1969